This invention relates to sheet inverting and stacking apparatus and in particular to the inverting and stacking of sheets produced from automatically reproducing machines. More specifically it relates to a simple device which serves to transport copies produced from an automatic reproducing machine to an output station and collect them in a collated and registered fashion.
In many automatic copying machines the geometry of the machine elements is such that with the paper path the copies produced have the image on the top side. Thus sequential copies enter the collecting tray with the copy or image side up. This is satisfactory if only a single copy of a single image is desired or if multiple copies of a single image is desired. In both cases, no distinction between sequential copies is required and all copies may be readily collected with the image side up. It is also satisfactory if the original documents fed to the copying machine are fed in reverse order, last or bottom sheet first and first or top sheet last. In this instance the collected set has the top sheet face up on top and the bottom sheet face up on the bottom of the set. However, in most instances of copying sets of documents, the set is face up with top sheet on the top and if copied according to normal procedures, the top sheet number one is copied, producing a copy face up and a set so produced has sheet number one face up on the bottom and the last sheet face up on the top. It can therefore be seen that it is desired to obtain the copies in the same order as the original set so that in the set produced by the copying machine the last sheet is on the bottom of the set and the top sheet is on the top of the set, both being face up. In addition, in electronic printing it is also advantageous to be able to print from the first page to the last page in order since if you print from the last sheet to the first sheet the substance of the first to last pages must be stored in the printers memory thereby increasing the size and cost of the memory required.
This result may be accomplished in copying a set of sheets if the top sheet, number one sheet, is fed first to be copied and the copy produced which is image side up is inverted such that the image is on the bottom side. With copying of successive sheets of a set and inverting each copy the final set is collected face down with the top sheet on the bottom and the bottom sheet on the top.